<template>
	<div class="el-tree-select">
		<el-select
				ref="treeSelect"
				v-model="valueId"
				:clearable="true"
				:filter-method="selectFilterData"
				:filterable="true"
				:placeholder="placeholder"
				style="width: 100%"
				@clear="clearHandle"
		>
			<el-option :label="valueTitle" :value="valueId">
				<el-tree
						id="tree-option"
						ref="selectTree"
						:accordion="accordion"
						:data="options"
						:default-expanded-keys="defaultExpandedKey"
						:expand-on-click-node="false"
						:filter-node-method="filterNode"
						:node-key="objMap.value"
						:props="objMap"
						@node-click="handleNodeClick"
				></el-tree>
			</el-option>
		</el-select>
	</div>
</template>

<script setup>

const {proxy} = getCurrentInstance()

const props = defineProps({
	/* 配置项 */
	objMap: {
		type: Object,
		default: () => {
			return {
				value: 'id', // ID字段名
				label: 'label', // 显示名称
				children: 'children' // 子级字段名
			}
		}
	},
	/* 自动收起 */
	accordion: {
		type: Boolean,
		default: () => {
			return false
		}
	},
	/**当前双向数据绑定的值 */
	value: {
		type: [String, Number],
		default: ''
	},
	/**当前的数据 */
	options: {
		type: Array,
		default: () => []
	},
	/**输入框内部的文字 */
	placeholder: {
		type: String,
		default: ''
	}
})

const emit = defineEmits(['update:value'])

const valueId = computed({
	get: () => props.value,
	set: (val) => {
		emit('update:value', val)
	}
})
const valueTitle = ref('')
const defaultExpandedKey = ref([])

function initHandle() {
	nextTick(() => {
		const selectedValue = valueId.value
		if (selectedValue !== null && typeof (selectedValue) !== 'undefined') {
			const node = proxy.$refs.selectTree.getNode(selectedValue)
			if (node) {
				valueTitle.value = node.data[props.objMap.label]
				proxy.$refs.selectTree.setCurrentKey(selectedValue) // 设置默认选中
				defaultExpandedKey.value = [selectedValue] // 设置默认展开
			}
		} else {
			clearHandle()
		}
	})
}

function handleNodeClick(node) {
	valueTitle.value = node[props.objMap.label]
	valueId.value = node[props.objMap.value]
	defaultExpandedKey.value = []
	proxy.$refs.treeSelect.blur()
	selectFilterData('')
}

function selectFilterData(val) {
	proxy.$refs.selectTree.filter(val)
}

function filterNode(value, data) {
	if (!value) return true
	return data[props.objMap['label']].indexOf(value) !== -1
}

function clearHandle() {
	valueTitle.value = ''
	valueId.value = ''
	defaultExpandedKey.value = []
	clearSelected()
}

function clearSelected() {
	const allNode = document.querySelectorAll('#tree-option .el-tree-node')
	allNode.forEach((element) => element.classList.remove('is-current'))
}

onMounted(() => {
	initHandle()
})

watch(valueId, () => {
	initHandle()
})
</script>

<style lang='scss' scoped>
@import "@/assets/styles/variables.module.scss";

.el-scrollbar .el-scrollbar__view .el-select-dropdown__item {
	padding: 0;
	background-color: #fff;
	height: auto;
}

.el-select-dropdown__item.selected {
	font-weight: normal;
}

ul li .el-tree .el-tree-node__content {
	height: auto;
	padding: 0 20px;
	box-sizing: border-box;
}

:deep(.el-tree-node__content:hover),
:deep(.el-tree-node__content:active),
:deep(.is-current > div:first-child),
:deep(.el-tree-node__content:focus) {
	background-color: mix(#fff, $--color-primary, 90%);
	color: $--color-primary;
}
</style>
